# Day 87: Projectile Practical, Energy Problems, & Board Meeting

AP Physics 1: Projectile Practical

Students finished predicting where a marble rolled off a lab table will hit the floor. Once students have a success, I gave them a lighter marble and asked them to predict where it will land without taking any new measurements.

Physics: Energy Problems

Students worked on calculations using conservation of energy. This was a tougher leap than I expected given how easily students got the hang of setting up conservation of momentum problems from bar charts. I think a card sort similar to the one we did for momentum would have been a good stepping stone.

Chemistry Essentials: Board Meeting

Students had a board meeting with their results from yesterday’s lauric acid lab. I had students collect data for the acid both melting and freezing, which made for a good visual of how similar those processes are. Students also made some good connections to last week’s activity in Pivot Interactives. I think starting with the cleaner data helped students to see the patterns in their data and there was some great conversation about why everyone had the same temperatures on their flat sections today while different groups got different temperatures on their graphs last week.

# Day 86: Projectile Practical, Bouncy Ball CER, & Lauric Acid Phase Change

AP Physics 1: Projectile Practical

Students started working on predicting where a marble rolled off the edge of a table will hit the floor. As a wrinkle, I left it open how to set up a ramp to launch a marble and how to measure the horizontal velocity, then had students write a procedure. Groups exchanged procedures with the goal that they should get the same velocity as the group who wrote the original procedure. My goal is for students to get some low-stakes feedback on this kind of writing.

Physics: Bouncy Ball CER

Students finished up with the bouncy ball lab we’ve been working on and whiteboarded CER statements for what is dissipating the bouncy ball’s energy. There was good consensus that the impact has a much bigger effect than air resistance. We used a worksheet to scaffold the pre-work for this activity, so there wasn’t as much variety as when I leave it wide open, but I think students were more successful than they would have been without it.

Chemistry Essentials: Lauric Acid Phase Change

Students collected data for phase changes of lauric acid. A few groups weren’t stirring, which made their data messier, but the patterns are pretty clear overall, even on the data table.

# Day 71: Unbalanced Forces Practical, Mistakes Whiteboarding, & Density Practical

AP Physics 1: Unbalanced Forces Practical

Since tomorrow’s assessment will include a second shot at our unbalanced forces learning target, we did a practical where students used unbalanced forces and constant acceleration to predict the velocity of a cart after it traveled a certain distance down a ramp. While we haven’t really dug into energy calculations yet, I did encourage students to try doing it as an energy problem if they had time, and the groups that tried it were excited to see the same answer two different ways.

Physics: Mistakes Whiteboarding

Students did mistakes whiteboarding to go over yesterday’s problems; not surprisingly, it went very quickly. I also didn’t have to get on students’ case about units or well-labeled diagrams, since they are at a point where they find it useful to see and were asking each other for that information when someone left it off.

I noticed a couple of groups in one section had started some interesting notation for their unknown I haven’t seen before; students really, really like to use x for their unknown, which I push back on, but these groups were using x plus a unit for their unknown. I can’t quite decide whether I like it; using x as an unknown does get in the way of using x to represent position, so I know I’d rather they use the standard variable. On the other hand, seeing the units written out for the unknown helped a lot of students see what math they needed to do and the students I talked to were very clear that “x m/s” represented how many meters the object traveled for every second, which the students just using v were not as consistently clear about. I’m trying to decide whether the potential value here outweighs the hurdles it may cause down the line; one option is to let them leave the units, but push they should still use the standard variable (like “v m/s” here). I don’t see myself ever introducing this kind of notation, but I’m also not sure I need to get students away from it if they find it useful.

Chemistry Essentials: Density Practical

As a practical to wrap up the density unit, I asked students to plan an experiment they could use to answer either whether the shape of an object impacts its density or whether the volume of an object impacts its density. It went about as I expected; initially, students were uncomfortable with how open-ended the task was, but, once they got started, they moved forward easily with the task. I think the challenge had more to do with students’ discomfort with this kind of task than their ability to complete it.

# Day 56: Final Exams

Today was our first day of final exams.

AP Physics 1: Practice Exam

I don’t actually have any AP Physics sections until tomorrow, but they will be taking roughly half of a practice exam. I trimmed it to fit into the 90 minute blocks we have for final exams, rather than 3 hours, as well as to limit it to material we’ve covered so far this year.

Physics: Lab Practical

Students took an individual final, then completed the “Catch the Loot” practical in small groups. Time was tight, so I didn’t have any groups today that were able to test their calculation. Given how satisfying this result is, it will be worth looking at how to adjust the timing if we repeat this lab next year. A lot of students will switch hours when the new term begins Monday, with many students even switching between me and the other physics teacher, so unfortunately it won’t be practical to give them the opportunity to try their prediction when the new term starts Monday.

Chemistry Essentials: Density Practical

Students took a short individual test, then did a density practical in groups. After finding the volume of a cylinder turned out to be a major barrier for a lot of students on a lab in September, I ordered some plastic centimeter cubes thinking they might make the lab more accessible. I decided the final would be a good opportunity to test out using them for the density lab and the results came out very nicely.

# Day 42: Problems, Practical, & Bohr Model

AP Physics 1: Problems

Students took the plunge to solving problems for objects with a constant acceleration. There was a great moment in one class where a group was struggling with a problem, and a student said “I’m gonna be [calculus teacher]!” He then proceeded to walk the graph while describing his motion to the rest of the group, which was just what they needed to figure out the problem. Thanks, Ms. Hyers!

Physics: Practical

Students did a lab practical where they needed to calculate how much mass to hang off a string in order to balance the forces on a cart on a ramp. Students tested their calculations using mass sets that went down to 10 g, which got them close enough to be satisfying.

Chemistry Essentials: Bohr Model

Students whiteboarded yesterday’s problems connecting the Bohr model of the atom to the periodic table. I remembered today that I want to re-work the problems I have to make the periodic trend in valence electrons pop out. The students who were checked in were feeling very confident by the end of the hour today. The trouble is I’m seeing more and more students check out; I’m wondering if another round of one-on-one conferences might help some students get more engaged by making it clear that they can still improve their grade.

# Day 36: Ramps, Interaction Problems, & Atomic Models

AP Physics 1: Ramps

Students collected position vs. time data for a cart on a ramp. I can tell that I did a better job introducing photogates than I have in the past because students flew through the data collection with nice looking results.

Physics: Interaction Problems

Students worked on some real-life balanced force problems based on Kelly O’Shea’s. There were some students who made really nice connections to the labs we’d done; there was a great moment when I heard a student use the “for every” statement we made about the slope in the force of gravity lab to figure out a station. One thing I’m thinking about is I had students start at a random station, then rotate through, but they build nicely enough that it could be helpful to figure out a way for all students to do them in order.

Chemistry Essentials: Atomic Models

Students did a reading on the main historical models of the atom. I like that students recognized that at each stage, new evidence showed a major limitation in the previous model, but I have yet to find a reading or other atomic models activity that doesn’t reinforce the myth of the “lone genius”. Afterward, we got out the gas tubes and diffraction gratings to see some of the evidence for the Bohr model.

# Day 7: Dueling Buggies, Board Meeting, & Volume

AP Physics 1: Dueling Buggies

Students predicted where two buggies would collide based on their starting points and speeds. It was interesting to see how different sections approached this problem; most of the groups in my 2nd hour used motion maps while almost all of my 4th hour used position vs. time graphs. When my 4th hour discussed the buggy paradigm lab, students brought up the fact that some of the graphs intersected, with one even bringing up that position vs. time graphs can be used to elegantly solve the classic two trains problem.

Physics: Board Meeting

Students wrapped up the buggy lab and we had our board meeting. Before the board meeting, I once again had students do a gallery walk and jot some notes down on their lab sheet, which lead to some really good conversation during the board meeting. The downside is students are using the gallery walk to ask questions I’d normally hope to hear during the whole-class board meeting, like asking about what a group was doing when they collected data that gave a negative slope, but students bringing up those points during the whole-class phase, so it doesn’t feel like a big downside.

Chemistry Essentials: Volume

Today, students found a relationship between the amount of water displaced and a solid’s volume in cubic centimeters to get at the equivalence of milliLiters and cubic centimeters. I haven’t had great results with the Modeling Instruction volume lab, so this year I cut some rods from the metals teacher into short sections so that students only needed to find the volume of cylinders. I like that the lab I did today uses the same version of water displacement they’ll use later on, but the math was a struggle for a lot of students. About half of my groups finished data collection and the other half only got one data point because they were caught up calculating the volume. I need to keep working on how to make this lab accessible to all of my students.

# Day 153: Levitating Globe, Pinhole Viewers, & Hollow Pennies

AP Physics: Levitating Globe

The approach I’ve fallen into in order to give students time for their final projects while embedding some review for the students who will be taking the AP Physics 1 exam on the make-up date. Today, I got out a globe that floats in a magnetic stand and asked students to predict what should happen to the reading on a balance when the globe is removed, an idea I got from Kelly O’Shea. One group did a thought experiment where the magnet was replaced with a spring supporting the globe to reason their answer and had a great conversation.

Physics: Pinhole Viewers

We discussed some of the results of yesterday’s lab, focusing on how a ray diagram can explain the observations students made. Students are pretty quickly getting then hang of making sense of these diagrams.

Chemistry Essentials: Hollow Pennies

Students did a conceptual lab practical on activity series today. I gave students an activity series for metals, then asked them to predict whether copper or zinc is more likely to react with hydrochloric acid. Then, I gave each student a penny with a wedge filed into it to test their prediction. I also showed students the hollow remnants of a penny that had been left in 12M hydrochloric acid for a few hours.

# Day 137: Toilet Paper Practical, Snakey Springs, & Limiting Reactant Hardware

AP Physics: Toilet Paper

Students finished working on the lab practical we started yesterday. Students did a lot of connecting ideas, which was great. I added a question asking students to calculate the final velocity of their unrolling roll using the velocity time graph and using energy, which I’m hoping to use to introduce rotational kinetic energy tomorrow.

Physics: Snakey Springs

My plan was to whiteboard yesterday’s lab, but most groups had either a linear or quadratic relationship between wavelength and frequency; a lot of students seemed distracted during yesterday’s pre-lab discussion, and I should have taken the time to bring their focus back rather than plowing ahead. We took a few minutes to talk about whether the graphs groups have make sense, then revisited the pre-lab discussion and re-did the data collection. I’ve had some other labs this tri we needed to re-do because of poor results, so I need to think about how to do a better job of making sure the lab goes well the first time around.

Turns out my heavy ring stands work well for holding one end of a snakey spring

Chemistry Essentials: Limiting Reactants Hardware

We revisited the nuts, bolts, and washers and the “reaction” used to introduce stoichiometry to explore more with limiting reactants. I had a few students who were bothered that there isn’t a simple rule they can always use to immediately identify the limiting reactant, but they were still able to see the kinds of approaches I wanted them to.

# Day 136: Toilet Paper, Snakey Springs, & Limiting Reactants

AP Physics: Toilet Paper

I started by having students whiteboard some model summaries. I started with linear motion, then asked students to add the angular version of each representation. This seemed to help students draw connections between linear and angular motion. Afterward, students started working on a lab practical to predict where to start an unrolling roll of toilet paper so it hits the ground at the same time as a toilet paper roll dropped from a given height.

Physics: Snakey Springs

To introduce waves, students played around with snakey springs to look for ways to change the behavior of the waves and get some data for a relationship between wavelength and frequency. Today was one of the first days it was 60 degrees all day and there wasn’t much snow on the ground, so I took the lab outside and a lot of students used sidewalk chalk to help with their measurements. There were also some good observations of the shadows; one group making cycloid waves noticed their shadow looked the same as the shadow for 2D waves.

Chemistry Essentials: Limiting Reatants

Students used a PhET simulation to start building some ideas about limiting reactants. The class was much rowdier than usual; the class meets the last period of the day, and I think the nice weather was making a lot of them restless. The concrete visualizations did seem to help a lot of students start making sense of limiting reactants.